SEED-BEARING PLANTS 
483 
believed to be derived. The method of pollination in 
normal flowers is illustrated in Fig. 370. 
424. Composite Family (Composite). The composites 
represent the highest development of dicotyledons. The 
flowers are borne on a common receptacle in a compact 
FIG. 367. Sections of flowers of the toad-flax (Linaria vulgaris). 
A, front view; a, anthers; s, stigma; , nectar-gland. B, side view; o, 
ovary. 
"head," giving the appearance, not so much of an in- 
florescence as of a compound flower, whence the family 
name, assigned by early botanists, who did not understand 
the morphology of the head. 
The heads are surrounded by a circle of bracts, called 
an involucre. The bracts which often occur on the re- 
